Software-defined networking (SDN) and Network Functions Virtualization (NFV) have revolutionized the traditional communication network architectures and have transformed the way communication service providers (CSPs) design their network infrastructure and services. NFV is a network architecture concept that virtualizes classes of network functions into building blocks that can be connected, or chained together, to create communication services.
The initial interest in introducing SDN and NFV into communication services has been driven by the desire to lower capital costs by replacing dedicated network hardware with generic computing platforms, and to lower operating costs by leveraging cloud automation tools. As the revolution has progressed, focus has shifted toward a foundational transformation in managed communication services, a migration toward a telecommunication (telco) cloud, and the emergence of distributed virtualized infrastructures.
Typical NFV implementations include multiple virtualized network functions (VNFs). A network operator, for example, may deploy NFV Infrastructure (NFVI) in the form of one or more computing devices to apply, to data traffic traversing a computer network, network functions such as firewall, carrier grade network address translation (CG-NAT), performance enhancement proxies for video, transport control protocol (TCP) optimization and header enrichment, caching, and load balancing. Each of these network functions may be performed by a virtualized network function, which may be executed by one or more virtual machines, containers, or other execution environment of the NFV Infrastructure. In this way, virtualized network functions may be executed by servers, switches, storage devices, and cloud computing infrastructure, instead of having custom hardware appliances for each network function.